#pragma ident "$Id$"

//============================================================================
//
//  This file is part of GPSTk, the GPS Toolkit.
//
//  The GPSTk is free software; you can redistribute it and/or modify
//  it under the terms of the GNU Lesser General Public License as published
//  by the Free Software Foundation; either version 2.1 of the License, or
//  any later version.
//
//  The GPSTk is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU Lesser General Public License for more details.
//
//  You should have received a copy of the GNU Lesser General Public
//  License along with GPSTk; if not, write to the Free Software Foundation,
//  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
//
//  Copyright 2004, The University of Texas at Austin
//
//============================================================================

//============================================================================
//
//This software developed by Applied Research Laboratories at the University of
//Texas at Austin, under contract to an agency or agencies within the U.S.
//Department of Defense. The U.S. Government retains all rights to use,
//duplicate, distribute, disclose, or release this software.
//
//Pursuant to DoD Directive 523024
//
// DISTRIBUTION STATEMENT A: This software has been approved for public
//                           release, distribution is unlimited.
//
//=============================================================================

/**
 * @file RinexObsData.hpp
 * Encapsulate RINEX observation file data, including I/O
 */

#ifndef RINEXOBSDATA_HPP
#define RINEXOBSDATA_HPP

#include <vector>
#include <list>
#include <map>

#include "CommonTime.hpp"
#include "FFStream.hpp"
#include "RinexObsBase.hpp"
#include "RinexObsHeader.hpp"

namespace gpstk
{
/** @addtogroup RinexObs */
//@{

/// A structure used to store a single RINEX Data point.
#ifndef GPSTK_RINEXDATUM
#define GPSTK_RINEXDATUM
struct RinexDatum
{
    RinexDatum() : data(0), lli(0), ssi(0) {}
    double data;  ///< The actual data point.
    short lli;    ///< See the RINEX Spec. for an explanation.
    short ssi;    ///< See the RINEX Spec. for an explanation.
};
#endif // GPSTK_RINEXDATUM

/**
 * This class models a RINEX Observation Data Record.
 *
 * @sa gpstk::RinexObsStream and gpstk::RinexObsHeader.
 * @sa rinex_obs_test.cpp and rinex_obs_read_write.cpp for examples.
 */
class RinexObsData : public RinexObsBase
{
public:

    /// map from RinexObsType to RinexDatum.
    typedef std::map<RinexObsType, RinexDatum> RinexObsTypeMap;
    /// map from SatID to RinexObsTypeMap.
    typedef std::map<SatID, RinexObsTypeMap> RinexSatMap;

    gpstk::CommonTime time;    ///< the time corresponding to the observations
    /** Epoch flag has the following values
     * 0 ok
     * 1 power failure since previous epoch
     * 2 start moving antenna
     * 3 new site occupation (end moving antenna)
     *   at least MARKER NAME header record follows
     * 4 header records follow
     * 5 external event
     * 6 cycle slip record - same format as observation, but slips not data,
     *   and LLI and SSI are blank
     */
    short epochFlag;
    /** number of satellites in this observation, except when epochFlag = 2-5,
     * then the number of auxiliary header records to follow.
     */
    short numSvs;
    double clockOffset;      ///< optional clock offset
    RinexSatMap obs;         ///< the map of observations
    RinexObsHeader auxHeader;///< auxiliary header records (epochFlag 2-5)

    /// Constructor.
    RinexObsData() : time(gpstk::CommonTime::BEGINNING_OF_TIME) {}

    /// Destructor
    virtual ~RinexObsData() {}

    // The next four lines is our common interface
    /// RinexObsData is a "data", so this function always returns true.
    virtual bool isData() const
    {
        return true;
    }

    /**
     * A Debug output function.
     * Dumps the time of observations and the IDs of the Sats
     * in the map.
     */
    virtual void dump(std::ostream& s) const;

protected:
    /**
     * Writes a correctly formatted record from this data to stream \a s.
     * When printing comment records, you'll need to format them correctly
     * yourself.  This means making sure that "COMMENT" is at the end
     * of the line and that they're the correct length (<= 80 chrs).
     * Also make sure to correctly set the epochFlag to the correct
     * number for the type of header data you want to write.
     */
    virtual void reallyPutRecord(FFStream& s) const
    throw(std::exception, FFStreamError,
          gpstk::StringUtils::StringException);

    /**
     * This functions obtains a RINEX Observation record from the given
     * FFStream.
     * If there is an error in reading from the stream, it is reset
     * to its original position and its fail-bit is set.
     * Because of the Rinex Obs format, a RinexObsData record returned
     * might not have data in it.  Check the RinexSatMap for empty()
     * before using any data in it.
     * @throws StringException when a StringUtils function fails
     * @throws FFStreamError when exceptions(failbit) is set and
     *  a read or formatting error occurs.  This also resets the
     *  stream to its pre-read position.
     */
    virtual void reallyGetRecord(FFStream& s)
    throw(std::exception, FFStreamError,
          gpstk::StringUtils::StringException);

private:
    ///<Time corresponding to previous set of oberservations
    /// Used in cases where epoch time of a epoch flag==0
    static gpstk::CommonTime previousTime;

    /// Writes the CommonTime object into RINEX format. If it's a bad time,
    /// it will return blanks.
    std::string writeTime(const CommonTime& dt) const
    throw(gpstk::StringUtils::StringException);

    /**
     * This function constructs a CommonTime object from the given parameters.
     * @param line the encoded time string found in the RINEX record.
     * @param hdr the RINEX Observation Header object for the current RINEX file.
     */
    CommonTime parseTime(const std::string& line, const RinexObsHeader& hdr) const
    throw(FFStreamError);
}; // class RinexObsData

//@}

} // namespace

#endif
